Lightning risk assessment software
The tools engineers actually use to run an IEC 62305-2 risk assessment, compared on the things that decide an audit: which edition of the standard each one states it implements, whether it runs on one desktop or in a browser, and what each vendor publishes about price.
Every IEC 62305-2 assessment is the same arithmetic. What differs between tools is which edition of the standard they compute it on, and what you can prove afterwards.
The field is small. A handful of desktop packages, a few browser tools, one calculation module inside a larger electrical suite, and a very large number of spreadsheets. Most of them compute the method correctly. The differences that matter on a real project are narrower and less exciting than a feature list suggests: the edition of the standard behind the numbers, whether anyone can trace a coefficient back to the clause it came from, and whether the output is a report a reviewer will accept.
This page compares what we could verify. Every fact about another vendor's product below is taken from that vendor's own published material, and the source is named. Where we could not read a current vendor page, we say so rather than filling the gap. Software releases change, so treat this as a starting point and confirm anything decisive with the vendor before you buy.
What separates one tool from another
Four questions decide most of the choice. Price and platform sit below them, not above.
Which edition it computes on
The 2024 third edition changed the method, not just the wording. If the project is specified to the current edition, a result produced on the 2010 edition is a different result. This is the single question most worth asking a vendor, and the one their marketing pages answer least clearly. See what changed in IEC 62305:2024.
Whether you can see the working
A reviewer who questions one coefficient needs a better answer than a final number. Being able to open a figure and see the table or equation it came from is what turns a calculation into evidence. See traceable, not AI-generated.
What the auditor actually reads
The deliverable is a document, not a screen. Inputs, method, per zone results, the verdict against the tolerable value, and a place for an engineer to sign. See audit-ready risk reports.
Whether it fits where you work
National practice can change the arithmetic. Germany holds rp at 1, Greece holds PTWS at 1, and printed p.12 of IEC 62305-2:2024 lets national or local regulation fix the tolerable risk itself. See IEC 62305 around the world.
What each vendor publishes
Everything in this section comes from the named vendor's own material. Where we could not read a current vendor page, the card says so instead of guessing.
StrikeRisk
Long established desktop software for IEC and EN 62305-2, widely used in the UK and markets following British practice. The ABB data sheet we could read covers version 6.0 and is dated 2018. It describes Windows software installed on a workstation with a licence dongle, offers workstation and network licences, and shows sample report headings referencing BS EN 62305-2:2012, the second edition. It states a free 15 day trial. No price is published on ABB's own pages, and licences are sold by enquiry in workstation and network tiers. We could not load the live ABB product page despite several attempts, so we cannot confirm the current version, whether a newer release covers the 2024 edition, or whether inspection records are covered. If StrikeRisk has moved to the third edition since that data sheet, ask ABB rather than taking this page's word for it. More on StrikeRisk.
DEHNsupport Toolbox
A desktop Windows suite of four modules: the Risk Tool, the Distance Tool, the Air-Termination Tool and the Earthing Tool, so the risk calculation is one part of a wider set. DEHN states that the standards available in the Toolbox are based on Edition 1 and Edition 2 of IEC 62305-2. It is distributed as a downloadable executable and licensed on request, with no price published. Note that the DEHN Risk Tool people refer to is this module, not the separate DEHNrisk product below, and the two sit on different editions. More on the DEHN tools.
DEHNrisk
DEHN's newer browser based tool, and the one place in this comparison where a competitor publishes both current edition support and a price. Its page lists IEC 62305-2:2024 and EN IEC 62305-2:2024, describes access through a customer portal without installation effort, and states EUR 99 per year, with a 50 percent first year discount for existing Toolbox licence holders. A 60 day demo offers full functionality except that results cannot be printed.
Lightning Risk Assessment
A calculation within ETAP's wider electrical engineering platform rather than a standalone risk product, which makes it a reasonable fit for a team already modelling the whole electrical system there and an expensive route for a firm that only needs the assessment. ETAP's page for the calculation quotes IEC 62305-2: 2010. No price is published; the page offers a demo request.
Lightning Calculator
A browser calculator that lets the user choose the edition, offering both Edition 2.0 (2010) and Edition 3.0 (2024). It is presented as free to start using. Useful for a quick check on either edition. We did not verify what the exported output contains, so if the deliverable matters to you, confirm that before relying on it.
Calculus
A browser tool with projects saved to an account. INGESCO states plainly that using the software is completely free, which is unusual in this field and worth knowing about. Its page refers to IEC 62305-2 without naming an edition year, so if the edition matters on your project, ask before you rely on the result.
One tool we could not check: JEF Shield, from JEF Techno Solutions, appears in searches as a web based risk assessment tool, but every attempt to load its page failed, so we could not confirm which edition it computes on or anything else about it, and we have deliberately left it out of the comparison rather than describe it from second hand sources. Several lightning protection manufacturers publish design guides and hardware selection aids that are sometimes described as risk software; where we found no calculation tool on a vendor's own site, we have not listed one.
Spreadsheets, and why they persist
More IEC 62305 assessments are produced in spreadsheets than in any single piece of software. That is not a failure of judgement. The method is arithmetic, a spreadsheet implements arithmetic, and a careful engineer who owns the file and knows the standard can produce a perfectly sound result in one.
The problems are practical and they arrive with time rather than at the start. A file built against the 2010 edition does not notice that the standard has moved on. A copy taken for one project and edited becomes a second, quietly different, method. There is rarely a record of who changed a coefficient or why, which is exactly what a reviewer asks about. And the output has to be assembled into a report by hand every time, which is where the hours go.
The honest test is not whether spreadsheets can do the job. It is whether the specific spreadsheet in front of you is on the current edition, whether anyone can say who last changed a coefficient, and whether the version being used on this project is the one that was reviewed. If all three answers are good, keep it. If any of them is a shrug, that is the reason to move.
How to check an edition claim yourself
Vendor pages are often vague about the edition, and not always deliberately. A page written three years ago says what was true three years ago. Two checks settle it quickly.
First, ask for the exact standard designation the software prints on its own report, with the year. A tool on the current edition will print something like IEC 62305-2:2024 or EN IEC 62305-2:2024. A tool on the previous edition prints a 2006, 2010 or 2012 designation. This is more reliable than a marketing page, because the report heading is what a reviewer sees.
Second, ask a method question the editions answer differently. Does the tool take ground strike point density or lightning flash density as its density input? Does it produce a single risk R combining injury to people and loss from fire, or does it still present four separate risks? Does it have a frequency of damage F for the availability of internal systems? A tool on the third edition answers the first way to all three.
The tolerable risk is not a constant
Any tool that treats the tolerable risk RT as a hardcoded number is asserting something the standard does not. Clause 7.3 NOTE 1 of IEC 62305-2:2024 gives RT = 1×10-5 per year as a representative value of tolerable risk and allows another value once the case has been investigated in detail. Printed p.12 goes further, allowing national or local regulation to fix RT, the tolerable frequency of damage FT, and the Annex A, B, C and E calculation rules and parameter values.
So the representative figure is the default where nothing else applies, not a line the standard draws for every structure everywhere. When you evaluate a tool, check that you can change the tolerable value, and check that the report states which value was used. On a project where a regulator or specification names a different figure, a tool that cannot express it cannot produce the assessment you need.
What we built, and what we have not
Lumex is browser based software built on IEC 62305-2:2024, the third edition. It computes the risk of injury to people R and the frequency of damage F from the nine risk components, compares each against the tolerable value in force for the project rather than a hardcoded constant, and produces a branded report along with a periodic inspection record under IEC 62305-3. Every coefficient in the calculation can be opened to show the clause, equation or table it came from. The arithmetic is deterministic, so the same inputs give the same numbers every time, and no part of the risk figure is generated by a language model.
What we are not: Lumex is a much newer product than the desktop tools here, and it is sold as a per seat monthly subscription, 49 US dollars for Professional and 79 for Enterprise with a ten seat minimum, so Enterprise starts at 790 US dollars per month. We do not perform the NFPA 780 annex assessment, covered in NFPA 780 vs IEC 62305. We do not do earthing, separation distance or air-termination design as full modules, so a team that wants one package for all of that will find the DEHNsupport Toolbox covers more ground than we do. And we are a considerably newer product than the desktop tools here.
New to the method? Start with the IEC 62305-2 risk method, or try the free rolling sphere calculator with no signup. Designing the physical system rather than choosing a tool? See lightning protection system design.
Questions answered
What software is used for IEC 62305 risk assessment?
Which lightning risk assessment software supports IEC 62305-2:2024?
Does the edition of IEC 62305 my software uses actually matter?
Is there free lightning risk assessment software?
How much does lightning risk assessment software cost?
Can I do an IEC 62305 risk assessment in Excel?
What should I look for when choosing IEC 62305 software?
Is desktop or cloud better for lightning risk assessment?
Lumex computes the IEC 62305-2 method and shows the working. It does not certify a structure. You may not issue or submit a Lumex output until a competent person, qualified where the structure is located, has reviewed the inputs and the result and signed it.
The tolerable risk in IEC 62305-2 is not a fixed constant. Clause 7.3 NOTE 1 gives RT = 1×10-5 per year as a representative value of tolerable risk and adds that another value may be set once the case has been investigated in detail. Printed p.12 then lets national or local regulations fix RT, the tolerable frequency of damage FT, and the Annex A, B, C and E calculation rules and parameter values. Every Lumex assessment states the jurisdiction it was computed under and the values that applied.